A research project is proposed to investigate the effectiveness of a controlled antiobiotic releasing prosthetic heart valve in preventing post-operative occurrences of prosthetic heart valve endocarditis. This antiobiotic releasing heart valve will be evaluated in long term implantation studies and acute experiments, where the animals will be presented with a massive bacteremia by intravenous challenge. A pharmacokinetic analysis will be made on the resulting antibiotic concentration data in the serum, based on in vitro determined drug release kinetics. These results will be compared to analogous studies employing non-antibiotic loaded prosthetic heart valves and parenteral prophylactic antibiotic therapy. The acute prosthetic valve studies and experiments with bacteria coated vascular implants will be utilized to determine the relationship between bacterial infections and thrombus formation on vascular implant materials.